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Drone Solution for Automatically Scanning 1-deep Case Reserves

Case Reserves at Warehouses & DCs

While many warehouses and DCs focus on storing pallets, there are some who have a significant share of their racking devoted to case storage. Also known as carton storage or case reserve storage, this is a configuration where cases (not pallets) are stored in racks. Each case will be a packaged cardboard carton which in turn consists of multiple items.

Certain goods are more amenable to large-scale case reserves. Medical devices, such as sterilized implants, are high-value, low-volume items that require careful handling and temperature-controlled environments and are better stored as cases, instead of pallets. They may even be subject to regulatory standards w.r.t. such storage. Certain types of apparel (eg. infant clothes) are also stored as case/carton stock, given their size, weight, variety, and nature of consumer demand.

Case reserve rack storage has also been observed at smaller, regional 3PL facilities, where a large number of SKUs from multiple customers are stored to enable local fulfillment. In such cases, there are only a few pallets received for each SKU, which are then fully broken down and converted into case stock, stored in racks.

Single-Deep versus Multiple-Deep Case Storage

Warehouse managers, especially those that manage case reserves, have to carefully balance the tradeoff between the utilisation of rack space and the ease of pick, put-away and cycle count operations. Single-deep (also known as one-deep or 1-deep) storage is of course a common type of pallet racking in large distribution centers; however, it may make sense for case storage as well, where the speed & flexibility of pick & put-aways are more critical than maximizing the utilisation of space. This is especially true in warehouses and DCs which are in the e-commerce supply chain and have a very large range of SKUs, where velocities tend to be higher, and order fulfillment metrics take precedence over others.

Very Narrow Aisles (VNAs) vs. Traditional Aisles

A related challenge for managing case storage in a large warehouse is the choice of aisle widths. Traditional aisle widths have ranged from 8 feet to 11 feet, but are quite suitable for carton reserve racking. Thus, we see a consistent trend towards Very Narrow Aisles i.e. VNAs. Most VNAs tend to be 6 feet wide, however there are many instances of 5-feet wide aisles as well – again mainly for reserve case storage.

Such warehouses are designed to make optimal use of the available real estate, with the aisles designed to be not only very narrow, but also 30 feet or more in height.

The downside of architecting warehouse racking as VNAs is the operational costs of the material handling equipment required for picks and put-aways. Full pallets stored in VNAs require swing-reach trucks as the MHE; these can cost upwards of US$120,000 in capital investment. Moreover, they need specially trained operators and regular maintenance.

Nevertheless, single deep racking in VNAs remains the optimal configuration for case reserves at high-velocity warehouses and DCs.

Single-Deep Stocktaking via Manual Counts

Inventory counting – whether daily cycle counts or monthly/quarterly/annual wall-to-wall counts, remain an integral part of warehouse operations. For one-deep case storage in VNAs, inventory counts involve operators using special fork-lifts or swing-reaches to scan barcodes in every bin location – across the length and height of each rack in each aisle.

Unlike a full pallet racking configuration, where each bin location will have 2 barcodes to be scanned and mapped to their location, case storage will, of course, have tens of barcodes to be scanned, one each on every single case/carton.

The time to scan one bin location in a case reserve configuration, therefore, is likely to be multiple times that required to scan pallet barcodes! This manual inventory counting process often becomes prone to errors, given the proximity of numerous barcodes in a single location.

Manual inventory counts of case-stock are thus tedious, time consuming, and use up a lot of human resources and expensive equipment.

One-deep Inventory Scans Using Drones

With the availability of fully autonomous drone solutions, manual inventory counts can – finally – be replaced with automated aerial counts. A fleet of drones, flying autonomously in VNAs with case storage, can use their in-built cameras to capture images and video each bin location, read the barcodes in real time, and map them to their correct locations. Such aerial inventory scans are fast, accurate, safe, auditable and scalable – thanks to cost-effective off-the-shelf hardware combined with intelligent automation software.

Aerially collected images of each rack location also enable inventory managers to quickly identify empty bin locations. Drones can be deployed to scan a specified set of locations across multiple aisles (instead of all locations in one aisle) to help find particular SKUs that may be missing or that may be required to fulfill an urgent order.

Needless to say, the one limitation to deploying autonomous drones to scan front-facing barcodes is that multi-deep case reserves cannot be fully scanned using just the drone camera. It turns out that, in discussions with inventory stakeholders, there is tremendous interest in inventory drones – and a strong willingness to consider one-deep case reserve so as to benefit from more frequent, fully automated inventory counts.

While every high-bay warehouse with one-deep case stock in VNAs can benefit from deploying drone-based inventory counting, the most suitable ones are those where:

  • There’s at-least 50,000 square feet of VNA racking for single-deep carton storage
  • Inventory counts are (or are expected to be) relatively frequent
  • At-least 2 full-time equivalent resources are required for manual counts

In such facilities, the return on investment for aerial inventory counting can be of the order of 6 to 9 months! This does not even include the intangible benefits from safer counts, richer inventory data, auditable location-wise images, and the ability to easily scale up the frequency of wall to wall counts.

FlytWare PoC at an Apparel Warehouse

Driven by the need to accelerate their cycle counts, inventory stakeholders at a large apparel distribution center in the US partnered with FlytBase to pilot drone-based inventory counts – in VNAs with one-deep reserve case storage.

FlytWare drones were able to reliably, consistently, safely navigate in narrow aisles – fully autonomously. By scanning all front-facing barcodes correctly, and mapping them to the appropriate locations, FlytWare demonstrated the power of automated aerial scans for such inventory configurations.

Operating through an operator-friendly user interface, and seamlessly integrated with warehouse management systems via ODBC/API interfaces, FlytWare can immediately enhance the efficiency of inventory operations, and soon be expanded to multiple use-cases, besides cycle counts. With precision landing, autonomous charging and fleet management built-in, FlytWare’s fully autonomous aerial inventory scans can be deployed across dozens of aisles, and hundreds of thousands of racking storage.

Streamline your DC inventory audits, and honor your 3PL customer SLAs, by deploying drone solutions that come with live video feeds, date-wise image archives, and location-wise barcode data.

Write to us at or schedule a call with the FlytWare team.

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